The present disclosure relates to an air conditioner and a method of controlling the air conditioner.
Air conditioners optimally condition air in a predetermined space according to the uses and purposes thereof. Such an air conditioner includes a compressor, a condenser, an expansion device, and an evaporator, and performs a refrigerating cycle for compressing, condensing, expanding, and evaporating refrigerant, to thereby cool or heat the predetermined space.
The predetermined space may be variously changed according to areas where the air conditioner is used. For example, when the air conditioner is installed in a home or an office, the predetermined space may be an indoor space of a house or a building. When the air conditioner is installed in a vehicle, the predetermined space may be a passenger space.
When an air conditioner performs a cooling operation, an outdoor heat exchanger installed in an outdoor unit functions as a condenser, and an indoor heat exchanger installed in an indoor unit functions as an evaporator. On the contrary, when the air conditioner performs a heating operation, the indoor heat exchanger functions as a condenser, and the outdoor heat exchanger functions as an evaporator.
FIG. 1 is a block diagram illustrating a configuration of an air conditioner in the related art.
Referring to FIG. 1, an air conditioner 1 includes a set temperature input part 2 for inputting a set temperature of an indoor space, an indoor temperature sensor 3 that senses temperature of the indoor space, and a control part 7 that controls operations of a compressor 4, an outdoor fan 5, and an indoor fan 6, based on temperature information sensed by the set temperature input part 2 and the indoor temperature sensor 3.
The set temperature input part 2, the indoor temperature sensor 3, and the indoor fan 6 may be included in an indoor unit, and the compressor 4 and the outdoor fan 5 may be included in an outdoor unit.
For example, when a temperature value sensed at the indoor temperature sensor 3 is lower than a set temperature value input through the set temperature input part 2 during a heating operation of the air conditioner 1, the control part 7 may operate the compressor 4, the outdoor fan 5, and the indoor fan 6. The operation of the control part 7 may be performed until the temperature of the indoor space reaches the set temperature value.
When an air conditioner in the related art performs a heating operation, an outdoor heat exchanger, that is, an evaporator is frosted because of relatively low outdoor temperature. In detail, a surface temperature of the evaporator or the temperature of refrigerant flowing through the evaporator should be lower than the temperature of outdoor air for the evaporator to absorb heat from the outdoor air.
At this point, when the surface temperature of the evaporator decreases to be equal to or lower than dew-point temperature, condensate water is produced on an outer surface of the evaporator. When the surface temperature of the evaporator decreases to be equal to or lower than the freezing point, the condensate water is frozen to frost the outer surface of the evaporator.
A frost amount of the outer surface of the evaporator heavily depends on humidity of the outdoor air. That is, as the humidity of the outdoor air increases, the frost amount increases.
To defrost the evaporator, the air conditioner performs a defrosting operation, that is, a reverse cycle operation. At this point, the heating operation is restricted. Thus, as the number of times of performing the defrosting operation or a time period taken to perform the defrosting operation is increased, a heating performance is decreased. As a result, it is preferred to minimize the number of times of performing the defrosting operation and the time period taken to perform the defrosting operation.
However, such air conditioners in the related art just perform the defrosting operation according to a predetermined time interval and do not consider a humidity condition of outdoor air which may affect the frosting. As a result, the defrosting operation is uniformly performed regardless of whether outdoor humidity is high or low, which jeopardizes optimization of defrosting efficiency and heating efficiency.